<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package	CodeIgniter
 * @author	EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
 * @license	http://opensource.org/licenses/MIT	MIT License
 * @link	https://codeigniter.com
 * @since	Version 3.0.0
 * @filesource
 */
defined('BASEPATH') or exit('No direct script access allowed');

/**
 * Interbase/Firebird Forge Class
 *
 * @category Database
 * @author EllisLab Dev Team
 * @link https://codeigniter.com/user_guide/database/
 */
class CI_DB_ibase_forge extends CI_DB_forge
{

    /**
     * CREATE TABLE IF statement
     *
     * @var string
     */
    protected $_create_table_if = FALSE;

    /**
     * RENAME TABLE statement
     *
     * @var string
     */
    protected $_rename_table = FALSE;

    /**
     * DROP TABLE IF statement
     *
     * @var string
     */
    protected $_drop_table_if = FALSE;

    /**
     * UNSIGNED support
     *
     * @var array
     */
    protected $_unsigned = array(
        'SMALLINT' => 'INTEGER',
        'INTEGER' => 'INT64',
        'FLOAT' => 'DOUBLE PRECISION'
    );

    /**
     * NULL value representation in CREATE/ALTER TABLE statements
     *
     * @var string
     */
    protected $_null = 'NULL';
    
    // --------------------------------------------------------------------
    
    /**
     * Create database
     *
     * @param string $db_name            
     * @return string
     */
    public function create_database($db_name)
    {
        // Firebird databases are flat files, so a path is required
        
        // Hostname is needed for remote access
        empty($this->db->hostname) or $db_name = $this->hostname . ':' . $db_name;
        
        return parent::create_database('"' . $db_name . '"');
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Drop database
     *
     * @param string $db_name            
     * @return bool
     */
    public function drop_database($db_name)
    {
        if (! ibase_drop_db($this->conn_id)) {
            return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
        } elseif (! empty($this->db->data_cache['db_names'])) {
            $key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
            if ($key !== FALSE) {
                unset($this->db->data_cache['db_names'][$key]);
            }
        }
        
        return TRUE;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * ALTER TABLE
     *
     * @param string $alter_type            
     * @param string $table            
     * @param mixed $field            
     * @return string|string[]
     */
    protected function _alter_table($alter_type, $table, $field)
    {
        if (in_array($alter_type, array(
            'DROP',
            'ADD'
        ), TRUE)) {
            return parent::_alter_table($alter_type, $table, $field);
        }
        
        $sql = 'ALTER TABLE ' . $this->db->escape_identifiers($table);
        $sqls = array();
        for ($i = 0, $c = count($field); $i < $c; $i ++) {
            if ($field[$i]['_literal'] !== FALSE) {
                return FALSE;
            }
            
            if (isset($field[$i]['type'])) {
                $sqls[] = $sql . ' ALTER COLUMN ' . $this->db->escape_identififers($field[$i]['name']) . ' TYPE ' . $field[$i]['type'] . $field[$i]['length'];
            }
            
            if (! empty($field[$i]['default'])) {
                $sqls[] = $sql . ' ALTER COLUMN ' . $this->db->escape_identifiers($field[$i]['name']) . ' SET DEFAULT ' . $field[$i]['default'];
            }
            
            if (isset($field[$i]['null'])) {
                $sqls[] = 'UPDATE "RDB$RELATION_FIELDS" SET "RDB$NULL_FLAG" = ' . ($field[$i]['null'] === TRUE ? 'NULL' : '1') . ' WHERE "RDB$FIELD_NAME" = ' . $this->db->escape($field[$i]['name']) . ' AND "RDB$RELATION_NAME" = ' . $this->db->escape($table);
            }
            
            if (! empty($field[$i]['new_name'])) {
                $sqls[] = $sql . ' ALTER COLUMN ' . $this->db->escape_identifiers($field[$i]['name']) . ' TO ' . $this->db->escape_identifiers($field[$i]['new_name']);
            }
        }
        
        return $sqls;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Process column
     *
     * @param array $field            
     * @return string
     */
    protected function _process_column($field)
    {
        return $this->db->escape_identifiers($field['name']) . ' ' . $field['type'] . $field['length'] . $field['null'] . $field['unique'] . $field['default'];
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Field attribute TYPE
     *
     * Performs a data type mapping between different databases.
     *
     * @param
     *            array &$attributes
     * @return void
     */
    protected function _attr_type(&$attributes)
    {
        switch (strtoupper($attributes['TYPE'])) {
            case 'TINYINT':
                $attributes['TYPE'] = 'SMALLINT';
                $attributes['UNSIGNED'] = FALSE;
                return;
            case 'MEDIUMINT':
                $attributes['TYPE'] = 'INTEGER';
                $attributes['UNSIGNED'] = FALSE;
                return;
            case 'INT':
                $attributes['TYPE'] = 'INTEGER';
                return;
            case 'BIGINT':
                $attributes['TYPE'] = 'INT64';
                return;
            default:
                return;
        }
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Field attribute AUTO_INCREMENT
     *
     * @param
     *            array &$attributes
     * @param
     *            array &$field
     * @return void
     */
    protected function _attr_auto_increment(&$attributes, &$field)
    {
        // Not supported
    }
}
